On Aug 30, 3:38*pm, Martin Gregorie
wrote:
On Thu, 30 Aug 2012 13:13:31 -0700, unclhank wrote:
The dumping of flaps seems to be well practiced in recovering from this
maneuver- I wonder who taught him this.

Its the recommended first action according to the ASW-20 POH, which goes
on to say that this action alone will often cause spin recovery, but that
if it doesn't, follow the standard procedure AFTER you've set the flaps
fully negative. The POH says the flap movement is to avoid exceeding VNE:
for positive flap settings VNE is quite low.

I'd also point out that sharply selecting fully negative flap reduces AOA
relative to the fuselage and airflow and so, as the POH says, may
initiate recovery by unstalling the wing.

Two points for those who haven't flown an ASW-20:

- ailerons and flaps are interconnected so that ailerons deflect with
* the flaps as the flap lever is moved except when selecting landing
* flap, when the ailerons go to a negative setting. This "crow mode"
* increases drag and helps to prevent tip stalling.

- the POH recommends always starting an aerotow with the flaps in
* position #2 (-6 degrees) for better low-speed control.

--
martin@ * | Martin Gregorie
gregorie. | Essex, UK
org * * * |

.....hmm, if we're talking about recovering from a low/slow spin, I'm
not sure if I'd be overly concerned with exceeding Vne. Good point
that in landing configuration, the ailerons go negative in the 20. My
question (hypothesis), however, was how did Bruno's spin recovery work
if the only thing he did was to dump his flaps (or go negative)? My
uneducated quess was that by doing so, either the full-opposite
ailerons became unloaded and/or the AOA was reduced. If I have this
right, Bruno's spin recovery wasn't an attempt to save his life as
much as it was to stay in the strong, gusting thermal somewhere at
stratospheric altitude, which he did with good skill. He knew his
ship's behavioral characteristics well from experience, even if the
glider may not have been in factory-tune (and he did mention
somewhere about adjusting its CG).

From the Soaring Safety Foundation website it looks like at one time
they were trying to implement Condor-based videos that simulated
safety-related issues like these. Perhaps a most effective/safe way of
visualizing what the ground looks like in a low-spin.